“Stronger” is a movie you need to see, no matter how much you think you don’t need to see it.

A less effective version of the same fact-based story, even with the same actors doing the same excellent work — it’s Jake Gyllenhaal’s finest, truest two hours on film — might creak and groan with “inspirational weepie” biopic machinery, over-engineered Big Moments and an arm-twisting, melodramatic approach to its subject. We’ve all had that feeling of being ushered in to movie church, a place of dutiful biopic worship. Director David Gordon Green, working from a script by John Pollono, will have none of it. He’s too interested in the day-to-day, moment-to-moment experience of the people on screen to risk falsifying that experience.

The subject here is Jeff Bauman, one of the 2013 Boston marathon bombing victims. A Costco deli employee, Bauman was near the finish line to cheer on his on-again, off-again girlfriend, Erin Hurley. After the smoke cleared from the explosions, Bauman was alive but his blast injuries required a double above-the-knee amputation. His rehabilitation, his relationships, his drinking (he’s now sober), his mixed pride and discomfort regarding his symbolic value as the emblem of “Boston Strong” — this is a lot for one movie, even if it stays close to its central figure’s perspective.

Pollono, primarily an actor (“This is Us”) making his feature screenwriting debut, adapts the Bauman memoir of the same title. Early scenes with Bauman’s boisterous, boozy family, crammed into a small apartment, evoke a great deal in a few quick strokes. Bauman as played by Gyllenhaal is a sweet-natured carousing townie who hasn’t grown up yet. Tatiana Maslany plays Hurley; she’s unerrring, and makes complete emotional sense in every beat. We see a tough, loving but wary partner, wondering if she should simply get used to on-again/off-again.

The bombing changes everything. Most of “Stronger” deals with the aftermath, and it’s a movie shrewdly attuned to the incremental degrees of progress and setback. Director Green fixes our attention in the early hospital scene when the bandages come off; it’s a long take, our viewpoint doubling as Bauman’s, and the framing and timing of it is exquisitely right. A lot has been written since “Stronger’s” Toronto International Film Festival premiere about Green’s efficient, pleasingly conventional technique, but it takes real skill to figure out a shot like this one. “Stronger” knows when to park it and let the actors share a frame for a little longer than we’re accustomed to these days. But it’s cinematic as well as dramatic.

In the months after he’s out of the hospital and struggling through rehab, “Stronger” honors the struggle with little things adding up to big ones. Hurley moves in with him, in that perilously cramped apartment, which seems all the smaller with Miranda Richardson’s slightly overripe performance as Bauman’s mother dominating the ensemble. The movie is an ode to familial and community support, but it’s hardly blind to the way some people exploited or explained Bauman’s ordeal.

At one point Bauman’s joined at the bar by a couple thanking him for “not letting the terrorists win.” His response, and Gyllenhaal’s complex, painful reading of the moment, pave the way for a later scene where Bauman and company, again at a bar, are confronted by drunks offering their theory that the marathon bombing was an Obama conspiracy. The movie has zero polemics to sell audiences; it comes closest, I suppose, in the moment when Bauman’s Costco manager (Danny McCarthy, good as always) comes to the apartment, and the family immediately assumes he’s there to tell Bauman that his services are no longer required. But he’s there to discuss insurance coverage. (Moral: Costco is a better company than most.)

There are telling, observant scenes of Bauman simply figuring out how to use the bathroom in a wheelchair, how to shower, when to clear out a sock drawer, and how to cope with waving a flag at a Bruins game when he’s still traumatized by the bombing. Gyllenhaal handles the physical demands of the part beautifully, with a steady, convincing digital assist from the effects team. The script returns in flashes to the nightmarish bombing at the most purposeful moments. Two later sequences ensure that tears will be shed at every screening of “Stronger”: Bauman’s reunion with the man who saved his life (Carlos Sanz, extremely moving), which Green finesses gracefully, without histrionics, and the scene of Bauman throwing out the first pitch at Fenway.

Green’s big hit to date was the stoner action comedy “Pineapple Express” but his best work can be found in “George Washington” and “Snow Angels.” If there’s a surprise in the tone of "Stronger,” it’s in how much humor, legitimate and tart, becomes a part of Bauman’s coping. “Stronger” seems to be a step forward for Green, marrying the sensitive-indie side of his career with the canny commercial instincts of his other work on film and television. Just about everything works in “Stronger.” And it has been many months since anyone could say that about a straight-ahead, meat-and-potatoes biopic.